Parasitic array antennas include one or more parasitic elements with an active/driven element. The driven element is connected to a transceiver but the parasitic elements are not. The amount of power gain and directivity of a parasitic array antenna may depend on the lengths of the parasitic elements and the spacing between them. In addition, radio frequency (RF) loading on the parasitic elements may also affect mutual coupling and reflectivity of parasitic array antennas.
Beamforming is a signal processing technique for directional signal transmission or reception. Such techniques may allow an antenna to produce high directional beams in the desired directions and nulls in the undesired directions, thereby increasing the signal-to-noise ratio in the desired directions and reducing interference and wastage of transmitted power in the undesired directions.
Existing solutions for forming nulls and directional beams for parasitic array antennas involve using adjustable reactance such as varactors (variable capacitance diodes) or the like. Such solutions are complicated and expensive. Therein lies a need for a low cost parasitic array antenna and a beamforming method for such a low cost parasitic array antenna.